lol the OP is/was? having the same problem, I gave him some suggestion on how what to look for and how to set timing using the ems without moving the distributor and so on. Its just a matter of having everything set up right to match the setup.
Biggest problem with the base calibrations is that even for the sentra calibrations all of them still have the ignition phasing CAS calibrations setup for rwd. Same when it goes for the 24-1 disk calibration that they tell you to set up. There is a couple changes you have to make to get the calibration setup for a single coil, not coil on plug and changes to the phasing as well.
Disable coils 2-4, set ignition using the setup menu, calibrate the tps and so on and some of the functions such as idle air control require enabling, same goes with knock input for timing changes with knock.
Once you learn the system and functions the car should idle and run pretty smoothly, I had no problems with timing jumping once I got mine running and I ran both single coil and COP at one point, both had no issues setting timing.